Muscle Strenght |Physical Exercise and Oxygen Uptake

Muscle strength, with training, will soon equate to physical demands. After they have been made to work harder and repeatedly, muscles gain bulk and power to cope with physical activity and exercise intensity. This response called hypertrophy. In direct contrast, muscles will decrease in size and lose strength after some time without activity. The response is called atrophy.

As well the above described effects of exercise and physical work or lack of it, has on the muscles, regular aerobic exercise, brings on additional beneficial results to the heart and blood vessels in their effort of delivering more oxygen to the muscle cells.

Regular exercise step-ups the efficiency and strength of the heart. The chambers of the heart can pump with each beat more blood and vacate more efficiently and the rate of beating at rest or below maximum effort decreases. The more physical exercise and therefore more fitness a person gains, the more physical exercise and work the body can do. Oxygen uptake is the indicator of how heavily a person is exercising. Based on the maximal oxygen uptake that a person can consume in a unit of time ml/min, the treadmill test is used to determine a person’s “Valium per time Oxygen Maximum” or maximal oxygen uptake (VO2 max).

During the treadmill test, as speed and level of difficulty gradually increases, ventilation and oxygen and carbon dioxide concentration of the inspired and expired air is measured. Treadmill test is curried out until the individual becomes deeply fatigued. Generally, most individuals can better their VO2 max, oxygen uptake, up 20% or more with physical exercise training. It is best to state exercise intensity as a percentage of VO2max since there are great individual differences in VO2max.

Various exercise intensity VO2max required:

Low intensity exercise: from 30 - 50% of VO2max (fast walk)
Moderate intensity exercise: from 50 - 65% of VO2max (jog)
High intensity exercise: from 70 - 80% of VO2max (marathon run) and
Very high intensity exercise: from 80 - 150% of VO2max

The extra 50% Adenosine Triphosphate (ATP) equal to 50% above 100% of VO2max it becomes available anaerobically from Phosphocreatine (PCr) and glycolysis.

An additional unit that energy output is sometimes is stated is Metabolic Equivalent Task or METs. One MET, equivalent resting energy expenditure is 1 kcal/kg/hr or approximately 3.5 O2/kg/min. Exercise given to individuals that are recouping from a heart attack are usually given in MET units. Standing is about 1.3 METs while a fast walk represents about 7 METs of energy expenditure. MET values for an activity are estimates; there are considerable individual variations.

muscle strength, physical exercise

Health and Fitness A Health Choice Destination Online.
© 2008 Health and Fitness All Rights Reserved

Welcome back!